> 1) Is it Saphron or something else?

Saffron. It's a spice; the most expensive spice you're likely to be able to buy in your local grocery store. It goes for several hundred dollars a pound.

> 2) What are all the lyrics, or where can I find them?

Err... umm...

> 3) What's the actual name of the song, Mello Yellow, or not?

I thought it was "Mad About Saffron," but I have no idea.

> 4) What does it have to do with clothes/GAP?

Err... nothing at all. Except that saffron is several hundred dollars a pound, and Gap clothing is several hundred dollars per stitch.